Panel Reaffirms Human Influence On Global Warming
On April 18, the Intergovernmental Panel on Climate Change (IPCC) released its latest draft report, which reaffirms and strengthens the major findings of its 1995 assessment of global warming.
The primary conclusion of both assessments: The body of evidence suggests "there has been a discernible human influence on global climate," primarily because of C02 emissions from burning fossil fuels.
According to the latest report, global average surface air temperatures have risen 0.7 to 1.5 °F since 1860 and are likely to rise an additional 1.8 to 9 °F by the end of the 21st century. IPCC is a collaboration of hundreds of scientists sponsored by the United Nations and the World Meteorological Organization.
Also on April 18, the National Oceanic & Atmospheric Administration (NOAA) reported that lllustration
the average U.S. temperature during the first quarter of the year was 1 °F higher than the previous record set in 1990, breaking all records set during 106 years of instrumental data. "Our climate is warming at a faster rate than ever before recorded," says NOAA Administrator D. James Baker. "Ignoring climate change and the most recent warming patterns could be costly to the nation. Small increases in global temperatures can lead to more extreme weather events, including droughts, floods, and hurricanes."
The rate and duration of the rise in average global temperature during the 20th century appear to have been the largest of any during the past 1,000 years, the IPCC report says.
Better statistical methods for analyzing data, better computer models, and a much better synthesis of paleoclimatic data have brought man-made climate change "out of the noise of natural variability," says Kevin E. Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research in Boulder, Colo., and a lead author of the draft report. A clear anthropogenic signal became obvious in about 1980, he says. 'What has happened in
the last decade in particular is outside the realm of what we would have predicted previously," he says.
The IPCC report lists several climate changes that its authors conclude have already taken place. These include an increase in annual precipitation over land in the mid- and high latitudes of the Northern Hemisphere—owing largely to increases in extreme precipitation events—and a decrease in the extent of snow cover in the Northern Hemisphere due to early melting. In addition, the thickness of Arctic sea ice in sum
mer or early autumn has declined 40% over roughly the past three decades, while the rate of sea level rise is now faster than at any time during the past 1,000 years.
For the 21st century, the report predicts relatively large increases in the heat index—the temperature the body feels—as temperatures
and humidity continue to rise. On a global basis, average precipitation intensities will strengthen, leading to increased risk of flooding, while drought
will be more likely in midcontinental areas.
by John Heiniy j ^ e largest uncertainty in modeling future climate arises from clouds, the report notes. Major questions remain about whether clouds will dampen or accelerate the temperature rise as they respond to higher levels of C02 in the atmosphere.
This IPCC report is the first of three; the other drafts are expected to be released next month. All will undergo independent scientific and government review and thus are likely to change before being finalized.
Bette Hileman
Republicans Set Their Science Budget House and Senate Republicans, over vocal Democratic protests, have completed work on H. Con. Res. 290, which is Congress' answer to the 2001 budget President Bill Clinton unveiled in February. Congress' version is slightly less generous to civilian research and development programs than Clinton's, which proposed increasing their funding 6% to $43.3 billion.
The resolution allows $42.9 billion, an increase of 5.3% over current fund
ing, for nondefense R&D in fiscal 2001, according to an analysis of the budget resolution issued by the American Association for the Advancement of Science's R&D Budget & Policy Program. The congressional budget resolution consists of five years' worth of two kinds of spending figures for 20 separate budget categories and is a bit hard to interpret, so the analysis is helpful.
The increase is attributable, AAAS says, to "a $1.1 billion increase for the National Institutes of Health and sufficient funds for a substantial 16.6% increase for R&D in the National Science Foundation and an 11.3% increase for nondefense R&D programs in the Department of Energy."
Other people, particularly those in Congress' Democratic minority, aren't quite so sanguine about the numbers. Sen. Tom Harkin (D-Iowa), for one, called the budget "woefully inadequate." During the floor debate on the final report on the resolution, which had been constructed during a conference that Democrats weren't invited to attend, Harkin pointed out that the Senate had unanimously voted three years ago to double NIH basic medical research in five years. Although the 2000 budget contained an increase of $2.3 billion that keeps the doubling on track, the current resolution is short by $1.6 billion of the $2.7 billion increase needed in 2001 to meet the doubling target, Harkin said.
According to the executive branch Office of Management & Budget, the resolution means that 20,000 new teachers won't be hired to reduce class size; 5,000 communities won't get federal aid targeted for school construction and modernization; and 14,000 fewer researchers, educators, and students will receive support from NSF than would have under Clinton's budget plan.
House Budget Committee Chairman John R. Kasich (R-Ohio) sees the budget resolution in quite a different light. "As we begin the 21st century," Kasich said in a statement, "this budget heads us in the right direction." He lauds the budget for keeping "Washington's mitts" off Social Security for the second year in a row, for continuing to pay down the federal debt by a trillion dollars over five years, and for providing for at least $150 billion in tax cuts over five years.
And Senate Budget Committee Chairman Pete V. Domenici (R-N.M.) pointed out to the critics that, under the resolution, NIH funding is going to get
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